The present embodiments relate to ink compositions suitable for printing marks or images on deformable substrates. In particular, disclosed herein is a stretchable aqueous ink composition that is more cost-efficient over formulations and provides robust images, even when printed on deformable substrates. These ink compositions can be used for ink jet printing.
Printing marks or images on deformable substrates is desirable for many applications, such as flexible medical devices, including surgical tools and implantable medical devices, robot skins, textiles (e.g., for stretchable swimming suits), rubber products such as tires, tubes, and cables, and the like. Consumable products based on rubbers and some textiles are also stretchable. Because of the highly deformable characteristic of the substrate, a stretchable ink is desired for printing on such substrates to achieve excellent image quality, image robustness, and image longevity. Another desirable attribute is an ink made from low cost materials.
Accordingly, while known compositions and processes are suitable for their intended purposes, a need remains for improved ink compositions with certain characteristics. Specifically, a need remains for low cost ink compositions suitable for printing on deformable or stretchable substrates. Additionally, a need remains for stretchable inks that form robust images which can be stretched and relaxed for a high number of cycles. There is also a need for stretchable inks that have good color stability. There is also a need for stretchable inks that exhibit good resistance to environmental factors such as light, chemicals, water, and oxidizing gases, thus generating hydrophobic and water-resistance images. Ideally, the stretchable ink would be suitable for both indoor and outdoor applications. Lastly, it would be desirable that such inks can be applied digitally.
Previous work by the inventors included a stretchable ink composition based on fluoroelastomer emulsions, as disclosed in U.S. patent application Ser. No. 13/182,579 to Wu et al., filed on Jul. 14, 2011, which is hereby incorporated by reference in its entirety and a stretchable ink composition based on polyurethane emulsions, as disclosed in U.S. patent application Ser. No. 13/495,915 to Wu et al., filed on Jun. 13, 2012, which is hereby incorporated by reference in its entirety.